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Bienzymatic systems are often used with electrochemical affinity biosensors to achieve high signal levels and/or low background levels. It is important to select two enzymes whose reactions do not exhibit mutual interference but have similar optimal conditions. Here, we report a sensitive electrochemical immunosensor based on a bienzymatic system consisting of β-galactosidase (Gal, a hydrolase enzyme) and flavin adenine dinucleotide-dependent glucose dehydrogenase (FAD-GDH, a redox enzyme). Both enzymes showed high activities at neutral pH, the reactions catalyzed by them did not exhibit mutual interference, and the electrochemical-enzymatic redox cycling based on FAD-GDH coupled with enzymatic amplification by Gal enabled high signal amplification. Among the three amino-hydroxy-naphthalenes and 4-aminophenol (potential Gal products), 4-amino-1-naphthol showed the highest signal amplification. Glucose, as an electro-inactive, stable reducing agent for redox cycling, helped in achieving low background levels. Our bienzymatic system could detect parathyroid hormone at a detection limit of ∼0.2 pg mL-1, implying that it can be used for highly sensitive electrochemical detection of parathyroid hormone and other biomarkers in human serum.

This study examined the possibility of estimating bed load discharge using a pipe hydrophone, an acoustic measurement sensor. To that end, a small-scale on-site hydraulic experiment device was built, and regression equations were developed based on the analysis of collision sound signals by bed load discharge, grain size distribution, and flow velocity change. They were classified into pulse and sound pressure integral-based regression equations according to the characteristic value of collision sound. To verify the regression equations, the calculated values of bed load discharge were compared with the actual values. The results showed that the regression equation based on the sound pressure integral had a higher accuracy than the pulse-based regression equation, and the error rate compared to the measured value was approximately 19%. The Index of Agreement (IoA) was found 0.83, indicating a good agreement between the changing trend and estimated value of bed load discharge. It is believed that sediment disasters could be prevented by incorporating various experimental conditions and establishing a corrective relationship with the actual bed load discharge in the river.

The high and selective catalytic activities of tyrosinase (Tyr) have frequently led to its application in sensitive biosensors. However, in affinity-based biosensors, the use of Tyr as a catalytic label is less common compared to horseradish peroxidase and alkaline phosphatase owing to the fact that phenolic Tyr substrates have yet to be investigated in detail. Herein, four phenolic compounds that have lower formal potentials than phenol were examined for their applicability as Tyr substrates, and three reducing agents were examined as potential strong reducing agents for electrochemical-chemical (EC) redox cycling involving an electrode, a Tyr product, and a reducing agent. The combination of 4-methoxyphenol (MP) and ammonia-borane (AB) allows for (i) a high electrochemical signal level owing to rapid EC redox cycling and (ii) a low electrochemical background level owing to the slow oxidation of AB at a low applied potential and no reaction between MP and AB. When this combination was applied to an electrochemical immunosensor for parathyroid hormone (PTH) detection, a detection limit of 2 pg/mL was obtained. This detection limit is significantly lower than that obtained when a combination of phenol and AB was employed (300 pg/mL). It was also found that the developed immunosensor works well in PTH detection in clinical serum samples. This new phenolic substrate could therefore pave the way for Tyr to be more commonly used as a catalytic label in affinity-based biosensors.

Assembly of bacterial flagellar hook requires FlgD, a protein known to form the hook cap. Symmetry mismatch between the hook and the hook cap is believed to drive efficient assembly of the hook in a way similar to the filament cap helping filament assembly. However, the hook cap dependent mechanism of hook assembly has remained poorly understood. Here, we report the crystal structure of the hook cap composed of five subunits of FlgD from Salmonella enterica at 3.3 Å resolution. The pentameric structure of the hook cap is divided into two parts: a stalk region composed of five N-terminal domains; and a petal region containing five C-terminal domains. Biochemical and genetic analyses show that the N-terminal domains of the hook cap is essential for the hook-capping function, and the structure now clearly reveals why. A plausible hook assembly mechanism promoted by the hook cap is proposed based on the structure., Matsunami et al determine the structure of the flagellar hook cap from Salmonella enterica by X-ray crystallography. The 3.3 Å resolution structure in combination with mutagenesis analysis provides insights into a putative hook assembly mechanism.

The commonly required properties of diffusive electron mediators for point-of-care testing are rapid dissolubility, high stability, and moderate formal potential in aqueous solutions. Inspired by nature, various quinone-containing electron mediators have been developed; however, satisfying all these requirements remains a challenge. Herein, a strategic design toward quinones incorporating sulfonated thioether and nitrogen-containing heteroarene moieties as solubilizing, stabilizing, and formal potential-modulating groups is reported. A systematic investigation reveals that di(thioether sulfonate)-substituted quinoline-1,4-dione (QLS) and quinoxaline-1,4-dione (QXS) display water solubilities of ≈1 m and are rapidly dissoluble. By finely balancing the electron-donating effect of the thioethers and the electron-withdrawing effect of the nitrogen atom, formal potentials suitable for electrochemical biosensors are achieved with QLS and QXS (-0.15 and -0.09 V vs Ag/AgCl, respectively, at pH 7.4). QLS is stable for >1 d in PBS (pH 7.4) and for 1 h in tris buffer (pH 9.0), which is sufficient for point-of-care testing. Furthermore, QLS, with its high electron mediation ability, is successfully used in biosensors for sensitive detection of glucose and parathyroid hormone, demonstrating detection limits of ≈0.3 × 10-3 m and ≈2 pg mL-1 , respectively. This strategy produces organic electron mediators exhibiting rapid dissolution and high stability, and will find broad application beyond quinone-based biosensors.

Propagating cascade reactions based on two proteases are promising for obtaining high signal amplification. However, in many cases, biosensors that use cascade reactions do not have low detection limits because of the inherent slowness of proteolytic reactions. Here, we report a sensitive electrochemical immunosensor using a high-signal-amplification method that combines a propagating cascade reaction and a redox cycling reaction. The cascade reaction uses ecarin and prothrombin: the ecarin label proteolytically converts inactive prothrombin into active thrombin, which then proteolytically liberates electroactive p-aminophenol (AP) from an AP-conjugated peptide. The liberated AP is electrochemically oxidized to p-benzoquinone imine (QI), regenerated by the reduction of QI by NADH, and then electrochemically reoxidized. This electrochemical-chemical (EC) redox cycling reaction significantly increases the electrochemical signal. The developed immunosensor is also compared with an immunosensor that uses only a propagating cascade reaction and an immunosensor that uses a single proteolytic reaction and an EC redox cycling reaction. The detection limits for thyroid-stimulating hormone (TSH) obtained using the three immunosensors are 3 pg/mL, 2 ng/mL, and 4 ng/mL, respectively, indicating that the newly developed immunosensor is more sensitive than the other two. The measured concentrations of TSH in clinical serum are found to agree well with those determined using a commercial instrument.

Enzyme-induced seedless Ag deposition is useful for selective Ag deposition and subsequent electrochemical Ag oxidation; however, a washing step is required after the deposition and before the electrochemical oxidation as the enzyme substrate can be oxidized during the electrochemical oxidation. Here, we report a fast Ag deposition method using a redox enzyme and quinone substrate that does not require a washing step. We found that the quinone substrate is reduced by a redox enzyme label, which is later oxidized to its original form via the reduction of Ag+ to Ag. Moreover, the quinone substrate is not electrochemically oxidized during the electrochemical Ag oxidation. We selected one diaphorase and 1,4-naphthoquinone from among seven redox enzymes (four diaphorases and three glucose-oxidizing enzymes) and six quinones, respectively. We applied this Ag deposition method for the detection of thyroid-stimulating hormone (TSH) over a dynamic range from 100 fg/mL to 100 ng/mL and found that TSH could be detected at concentrations as low as approximately 100 fg/mL in artificial serum. Therefore, the Ag deposition strategy developed in this study exhibits promising potential for ultrasensitive clinical applications.

Horseradish peroxidase (HRP)-based electrochemical immunoassays are considered promising techniques for point-of-care clinical diagnostics, but the necessary addition of unstable H2O2 in the enzymatic system may hinder their practical application. Although glucose oxidase (GOx) has been widely explored for in situ generation of H2O2 in HRP-based immunoassay, the GOx-catalyzed reduction of oxidized peroxidase substrate may limit the immunosensing performance. Here, we report a sensitive electrochemical immunosensor based on a choline oxidase (ChOx)-HRP cascade reaction. In this design, ChOx catalyzes the oxidation of choline, during which H2O2 is generated in situ and thus oxidizes acetaminophen (APAP) in the presence of HRP. The electrochemical behavior of APAP in the ChOx-HRP cascade was compared with that of the commonly used GOx-HRP cascade, which confirmed that ChOx could be a superior preceding enzyme for sensitive immunoassay based on the bienzymatic cascade. The developed ChOx-HRP cascade was also further explored for a sandwich-type electrochemical immunoassay of parathyroid hormone in artificial and clinical serum. The calculated detection limit was ~3 pg/mL, indicating that the ChOx-HRP cascade is especially promising for highly sensitive electrochemical immunoassays when APAP is used as the peroxidase substrate.

Metal nanoparticle surfaces are used for peroxidase- and oxidase-like nanozymes but not for esterase-like nanozymes. It is challenging to obtain rapid catalytic hydrolysis on a metal surface and even more so without a catalytically labile substrate. Here, we report that metal nanoparticle surfaces rapidly catalyze non-redox ester hydrolysis in the presence of redox H3 N-BH3 (AB). Metal hydrides are readily generated on a Pt nanoparticle (PtNP) from AB, and as a result the PtNP becomes electron-rich, which might assist nucleophilic attack of H2 O on the carbonyl group of an ester. The nanozyme system based on PtNP, AB, and 4-aminonaphthalene-1-yl acetate provides an electrochemical signal-to-background ratio much higher than natural enzymes, due to the rapid ester hydrolysis and redox cycling involving the hydrolysis product. The nanozyme system is applied in a sensitive electrochemical immunosensor for thyroid-stimulating hormone detection. The calculated detection limit is approximately 0.3 pg mL-1 , which indicates the high sensitivity of the immunosensor using the PtNP nanozyme.

Simple and sensitive competitive immunosensors for small molecules are difficult to obtain, especially in serum containing numerous interfering species (ISs) with different concentrations. Herein, we report a washing-free and sensitive (competitive) displacement immunosensor for cortisol in human serum, based on electron mediation of Os(bpy)2Cl2 between an electrode and a redox label [oxygen-insensitive diaphorase (DI)] (i.e., electrochemical–enzymatic redox cycling). The anticortisol IgG–DI conjugate bound to a cortisol-immobilized electrode is displaced by competitive binding of cortisol in serum and diffuses away from the electrode during incubation; therefore, the concentration of the displaced conjugate near the electrode becomes very low, even without washing. Electrochemically interfering ascorbic acid is converted to a redox-inactive species by ascorbate oxidase during incubation. The remaining bound conjugate mainly contributes to electrochemical currents. Compared with ferrocene methanol, Fe(CN)...

Catalytic precipitation and subsequent electrochemical oxidation or reduction of a redox-active precipitate has been widely used in electrochemical biosensors. However, such biosensors often do not allow for low detection limits due to a low rate of precipitation, nonspecific precipitation, loose binding of the precipitate to the electrode surface, and insulating behavior of the precipitate within a normal potential window. Here, we report an ultrasensitive electrochemical immunosensor for parathyroid hormone (PTH) detection based on DT-diaphorase (DT-D)-catalyzed formation of an organic precipitate and electrochemical oxidation of the precipitate. In the present study we found that DT-D can be used as a catalytic label in precipitation-based affinity biosensors because DT-D catalyzes fast reduction of 3-(4,-5-dimethylthiazo-2-yl)-2,5-diphenyltetrazolium bromide (MTT) to MTT-formazan precipitate; the MTT reduction does not occur in the absence of DT-D; and a high electrochemical signal is obtained at low potentials during electrodissolution of MTT-formazan precipitate. The immunosensor is fabricated using a silane copolymer-modified ITO electrode surface that is suitable for both efficient and strong adsorption of MTT-formazan precipitate. When the enzymatic MTT-formazan precipitation and subsequent MTT-formazan electrodissolution is applied to a sandwich-type immunosensor, PTH can be detected over a wide range of concentrations with a very low detection limit (∼1 pg/mL) in artificial serum. The measured concentrations of PTH in clinical serum samples showed high similarity with those obtained using a commercial instrument.

This paper reports on a study of LiNiZn-ferrite composite as a radiation absorbent material (RAM). The electromagnetic (EM) wave absorbers are composed of an EM wave absorbing material and a polymeric binder. The surface morphology, chemical composition, weight percent of the ferrite composite of the toroid sample, magnetic properties, and return loss are investigated using field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), and network analyzer. For preparing the absorbing sheet, chlorinated polyethylene (CPE) is used as a polymeric binder. The EM wave absorption properties of the prepared samples were studied at 4 - 8 GHz. We can confirm the effects of the thickness of the samples for absorption properties. An absorption bandwidth of more than a 10-dB return loss shifts toward a lower frequency range along with an increase in the thickness of the absorber.

The hormone estradiol (17β-estradiol, E2) plays an important role in sexual development and serves as an important diagnostic biomarker of various clinical conditions. Particularly, the serum E2 concentration is very low (10 pg/mL) in prepubertal girls. Accordingly, many efforts to develop a sensitive method of detection and quantification of E2 in human serum have been made. Nonetheless, current clinical detection methods are insufficient for accurate assessment of E2 at low concentrations (10 pg/mL). Thus, there is an urgent need for new technologies with efficient and sensitive detection of E2 for use in routine clinical diagnostics. In this study, we introduce a new E2 assay technique using a surface-enhanced Raman scattering (SERS)-based detection method. The SERS-based assay was performed with 30 blood samples to assess its clinical feasibility, and the results were compared with data obtained using the ARCHITECT chemiluminescence immunoassay. Whereas the commercial assay system was unable to quantify serum levels of E2 lower than 10 pg/mL, the limit of detection of E2 using the novel SERS-based assay described in this study was 0.65 pg/mL. Thus, the proposed SERS-based assay has a strong potential to be a valuable tool in the early diagnosis of precocious puberty due to its excellent analytical sensitivity.

In horseradish peroxidase (HRP)-based electrochemical immunosensing, an appropriate HRP substrate needs to be chosen to obtain a high electrochemical signal-to-background ratio. This is limited by the unwanted electrochemical reduction of H2O2, oxidation of the substrate, and the slow electrochemical reduction of the product. Herein, we report acetaminophen (AMP) as a new HRP substrate that allows for highly sensitive immunosensing. Electrochemical behavior and immunosensing performance using AMP are compared with those using the most popular HRP substrate, hydroquinone (HQ). To maintain a high electrocatalytic activity even at an electrode modified with an immunosensing layer, an indium tin oxide electrode partially modified with reduced graphene oxide is employed. AMP allows for a higher signal-to-background ratio than HQ, because the formal potential of AMP is 0.28 V higher than that of HQ and the redox reaction of AMP is as reversible as that of HQ, resulting in a lower detection limit in a sandwich-type immunoassay using AMP for thyroid-stimulating hormone detection. The calculated detection limit is ~0.2 pg/mL. The use of AMP as an HRP substrate is especially promising for highly sensitive electrochemical immunoassays.

Barnyard millet Miryang 3 [Echinochloa esculenta (A. Braun)] grains have recently been acknowledged for beneficial health properties due to phenolic ingredients and dietary fiber. This study has been con-ducted on the anti-diabetic activity of barnyard millet Miryang 3 which shows the strongest anti-in-flammatory activity among barnyard millet inhabiting in South Korea. When 80% ethanol (EtOH) ex-tract of barnyard millet Miryang 3 grains were orally administered into db/db diabetic mice for 8 weeks (600 mg/kg/day), the glucose level in blood following fasting appeared to be improved com-pared to the control group. The results of glucose tolerance test and blood lipid profile assay were similar to those of the metformin-administered positive control group. In addition, the level of body weight increase (8.54±2.24) was lower than the level of metformin-administered group (10.36±3.15); however, there was no subtle difference with negative and positive control groups in terms of food efficiency rates. In addition, total cholesterol levels of the 80% EtOH extract-administered group (160.7±7.6) were significantly reduced compared to the diabetic control group (229.3±47.8) and metfor-min-administered group (176.0±25.6). Consequently, these results show that barnyard millet grains al-leviates many of the diabetic symptoms in vivo non-insulin-dependent diabetes mellitus, and suggest that barnyard millet grains can be applicable in developing new functional food materials.

Enzyme-like nanocatalytic reactions developed for high signal amplification in biosensors are of limited use because of their low reaction rates and/or unwanted side reactions in aqueous electrolyte solutions containing dissolved O2. Herein, we report a nitrosoreductase-like catalytic reaction, employing 4-nitroso-1-naphthol, Pd nanoparticles, and H3N–BH3, which affords a high reaction rate and minimal side reactions, enabling its use in ultrasensitive electrochemical biosensors. 4-Nitroso-1-naphthol was chosen after five hydroxy-nitro(so)arene compounds were compared in terms of high signal and low background levels. Importantly, the nanocatalytic reaction occurs without the self-hydrolysis and induction period observed in the nanocatalytic reduction of nitroarenes by NaBH4. The high signal level results from (i) fast nanocatalytic 4-nitroso-1-naphthol reduction, (ii) fast electrochemical redox cycling, and (iii) the low influence of dissolved O2. The low background level results from (i) slow direct rea...

The most common enzyme labels in enzyme-linked immunosorbent assays are alkaline phosphatase and horseradish peroxidase, which, however, have some limitations for use in electrochemical immunosensors. This Article reports that the small and thermostable DT-diaphorase (DT-D) and electrochemically inactive 4-nitroso-1-naphthol (4-NO-1-N) can be used as a bifunctional enzyme label and a rapidly reacting substrate, respectively, for electrochemical immunosensors. This enzyme-substrate combination allows high signal amplification via rapid enzymatic amplification and electrochemical redox cycling. DT-D can convert an electrochemically inactive nitroso or nitro compound into an electrochemically active amine compound, which can then be involved in electrochemical-chemical (EC) and electrochemical-enzymatic (EN) redox cycling. Six nitroso and nitro compounds are tested in terms of signal-to-background ratio. Among them, 4-NO-1-N exhibits the highest signal-to-background ratio. The electrochemical immunosensor using DT-D and 4-NO-1-N detects parathyroid hormone (PTH) in phosphate-buffered saline containing bovine serum albumin over a wide range of concentrations with a low detection limit of 2 pg/mL. When the PTH concentration in clinical serum samples is measured using the developed immunosensor, the calculated concentrations are in good agreement with the concentrations obtained using a commercial instrument. Thus, the use of DT-D as an enzyme label is highly promising for sensitive electrochemical detection and point-of-care testing.

Phenolic compounds such as isoflavones contribute to the antioxidant properties of soybean. This study investigated differences in the phenolic content and antioxidant activity of ten soybean cultivars grown in two different locations in Korea. We observed a wide range of variation in total isoflavone and phenolic content by location and cultivar. The total isoflavone content of cultivars grown at Pyeongchang (sub-highland) was significantly higher than that in cultivars grown at Gangneung (lowland). In contrast, the total phenolic content of cultivars grown at Gangneung was greater than that of cultivars grown at Pyeongchang. The radical scavenging activity of DPPH was similar to that of the total phenolic content rather than that of the total isoflavone content. These results suggest that antioxidant activity of soybean was associated with phenolic compounds rather than isoflavones. To identify the individual antioxidant components, we used an on-line HPLC-ABTS + -based assay system, ESI/MS, and NMR. The results showed that the strongest antioxidant activity was linked to epicatechin.

In order to compare the anti-inflammatory effects of five selected cereal grains－proso millet, hwanggeumchal sorghum, foxtail millet, barnyard millet, and adlay－the inhibitory activities of 80% ethanol (EtOH) extracts obtained from the individual grains on lipopolysaccharide (LPS)-induced nitric oxide (NO) generation were investigated in RAW264.7 cells. The EtOH extract of barnyard millet (Echinochloa crus-galli var. frumentacea) grains exhibited more potent anti-inflammatory activity than that of the other grains. When the EtOH extract of barnyard millet grains was sequentially fractionated with n-hexane, methylene chloride (MC), ethyl acetate (EtOAc), and n-butanol, the majority of the anti-inflammatory activity was detected in the MC fraction, followed by the EtOAc fraction. Pretreatment with the MC fraction caused downregulation of the expression levels of iNOS- and COX-2-specific transcripts and proteins, as well as proinflammatory cytokine gene transcripts (IL-1β, IL-6, and TNF-α) in LPS-stimulated RAW264.7 cells. Additionally, the MC fraction could suppress not only the LPS-induced nuclear translocation of cytosolic NF-kB, but also the LPS-induced activation of MAPKs, such as ERK, JNK, and p38MAPK. Further analysis of the MC fraction by HPLC identified kaempferol, biochanin A, and formononetin as the major phenolic components. Both kaempferol and biochanin A, but not formononetin, could exert anti-inflammatory effect at the same concentrations as those of the MC fraction. Consequently, these results indicate that kaempferol and biochanin A are among the most effective anti-inflammatory phenolic components in barnyard millet grains. This finding suggests that barnyard millet grains and the MC extract enriched in kaempferol and biochanin A could be beneficial functional food sources that have an anti-inflammatory effect.

Background The prognostic value of the tumor burden characterized by the metabolic tumor volume (MTV) remains under investigation in nasopharyngeal carcinoma (NPC). The purpose of this study was to evaluate the prognostic value of the maximum standardized uptake value (SUVmax) and MTV according to metabolic volume threshold as measured by positron emission tomography (PET)/computed tomography (CT), and other clinical factors, in patients with NPC. Methods This study was a retrospective chart review. We evaluated the association of SUVmax, MTV2.5, MTV3.0, and other clinical factors with overall survival (OS) using Kaplan-Meier and Cox regression models. (MTV2.5 and MTV3.0 are the volume of hypermetabolic tissue within the regions of gross tumor volumes with a SUV value greater than the threshold values of 2.5 and 3.0, respectively.) Results Higher MTV2.5 of 31.45 cm3 and MTV3.0 of 23.01 cm3 were associated with an increased risk of death (hazard ratio [HR] = 5.028; p = 0.029), although no significant relationship was found between SUVmax and OS. Interestingly, MTV3.0 was associated with OS in both the differentiated and undifferentiated groups, although MTV2.5 was only associated with OS in the undifferentiated group. Among the clinical parameters, only radiotherapy was associated with longer OS (HR = 12.124; p < 0.001). Conclusion The MTV and radiotherapy could be prognostic values associated with OS. Particularly, MTV2.5 and MTV3.0 might be valuable metabolic parameters for predicting long-term survival in patients with NPC. Furthermore, MTV3.0 may be more useful because it can be applied irrespective of pathologic subtype.

HLA-DRB1 is the most important gene for rheumatoid arthritis (RA) susceptibility. The HLADRB1 shared epitope (SE) alleles that share conserved amino acid sequences and non-SE *09:01 allele account for about one-third of the genetic contribution to RA. We aimed to develop RA specific HLA-DRB1 genotyping microarray kit to achieve a 4-digit high resolution typing for the essential set of the susceptible DRB1 alleles in the RA. Korean RA patients (n=172) and controls (n=13) who performed HLA-DRB1 genotyping at 4-digit resolution by standard PCR-SBT method were enrolled. A total of 14 probes were designed for the RA specific HLA-DRB1 genotyping microarray. PCR products were hybridized with the probes which were covalently linked with a silylated glass slide of microarrays. HLA-DRB1 genotype was assigned using a signal table based on the scanned hybridization patterns. Using the RA-specific HLA-DRB1 microarray chip, we accurately determined the RA susceptible alleles at 4-digit resolution (*01:01, *04:01, *04:04, *04: 05, *04:08, *04:10, *09:01, *10:10) and all the other subtypes of *04 in Korean population (n=185). Microarray results from 185 subjects showed high concordance with conventional PCR-SBT method irrespective of genotypes of risk or non-risk alleles (N=181), except for ambiguity in four cases of *01:01/*04:06 genotype, in which the microarray results were *01:01 /*04:03 or *01:01/*04:06. We developed a cost-effective RA-specific HLA-DRB1 genotyping microarray chip which is accurate and useful in clinical aspects as well as research purpose for RA.

A specific and sensitive liquid chromatography-electrospray ionization tandem mass spectrometry method (LC-ESI- MS/MS) was developed and validated for the simultaneous quantification of porphyrins (coproporphyrin, pentacarboxylporphy- rin, hexacarboxylporphyrin, heptacarboxylporphyrin, and uroporphyrin) in human plasma and urine. Acidified plasma samples and urine samples were prepared by using liquid-liquid extraction using ethyl acetate and protein precipitation with acetonitrile, respectively. The separation was achieved onto a Synergi Fusion RP column (150 mm × 2.0 mm, 4 µm) with a gradient elution of mobile phase A (0.1% formic acid in 2 mmol/L ammonium acetate, v/v) and mobile phase B (20% methanol in acetonitrile, v/ v) at a flow rate of 450 µL/min. Porphyrins and the internal standard (IS), coproporphyrin I- 15 N4, were detected by a tandem mass spectrometer equipped with an electrospray ion source operating in positive ion mode. Multiple reaction monitoring (MRM) transitions of the protonated precursor ions and the related product ions were optimized to increase selectivity and sensi- tivity. The proposed method was validated by assessing selectivity, linearity, limit of quantification (LOQ), precision, accuracy, recovery, and stability. The calibration curves were obtained in the range of 0.1-100 nmol/L and the LOQs were estimated as 0.1 nmol/L for all porphyrins. Results obtained from the validation study of porphyrins showed good accuracy, precision, recov- ery, and stability. Finally, the proposed method was successfully applied to clinical studies on the autism spectrum disorder (ASD) diagnosis of 203 Korean children.

주거 공간에 건강관리에 필요한 서비스가 제공되는 것은 'aging in place'의 실현을 가속화할 것이다. 그리고 이러한 주거공간의 변화는 의료비를 절감하고 삶의 질을 향상하는 복지 측면에서도 중요하다. 본 연구에서는 고령자가 스스로 건강을 관리할 수 있도록 헬스케어 서비스(Healthcare service)를 아파트 단지 내에 적용하는 계획방안에 대해 도출하고 주거복지동의 첫 사업 대상지인 가양 7단지 영구임대주택 단지를 중심으로 내용을 전개하고자 한다. 먼저 거주자의 헬스케어 서비스 이용의향에 대해 조사하고 관심이 높은 응답자를 중심으로 실제 시범사업이 적용된 서비스의 사용모습 관찰 및 심층 인터뷰를 통해 추후 계획시 고려할 사항에 대해 도출하였다. 가양 7단지의 경우 유헬스케어 서비스에 대한 요구는 고령자보다는 고령자 진입층에서 더 강력하게 나타나지만 공통적으로 주호의 협소함으로 기기 설치 및 측정에 어려움을 느끼고 있었다. 관찰조사 결과 주호는 사용자세의 불편함으로 입식구조의 측정공간 계획이 필요하며 장비보관장소도 필요하다. 그리고 헬스케어 서비스를 위한 프로그램은 건강측정, 건강관리, 외부 시설과 연계된 시설로 나눠 계획할 수 있으며, 이는 건강측정 공간을 기본형, 즉 최소형으로 하여 점차 확대 적용할 수 있다. 가양 7단지의 경우, 별도의 복지 건물이 신축되므로 기능을 복합적으로 구성하는 혼합형의 프로그램을 적용할 수 있으며, 반자립 사용자에 대한 서비스까지 확대 적용하는 계획이 필요하다. 【Health care services in a residential area would accelerate the aging in place. In addition, these changes would play a key role in terms of reducing healthcare costs and leading a healthy lifestyle. The purpose of this study draws the design methodology of community facilities and each dwelling with healthcare services in apartment complex, which the elderly people will enjoy a better health status. This paper presents the result focused on the welfare building in Gayang 7th apartment complex. The intention to receive healthcare services was investigated by occupants. Moreover, design requirements were drawn through in-depth interviews and the state observation to use the service. In the complex, stronger intention to serve the u-Healthcare services was shown to the pre elderly group than the elderly. Both of them had a problem to use and keep the health equipment due to the fact there is not enough space in the unit. Reporting the observation results, the upright-posture furniture attaching the healthcare equipment and the equipment storage should be prepared in the unit. In the public space, the program for these healthcare services can be divided into three parts, i.e. the health status measurement, the healthcare, and the service connected to the surrounding facilities. The health status measurement can be the basic to the health services and its function should be gradually extended. In the complex, the hybrid type with various functions could be applied owing to a new building for welfare; moreover, semi-independent user should be able to receive the home healthcare service.】

The residential environment of old and deteriorated public rental housing has been improved for preventing house deterioration through the facility improvement projects during the recent three years. The purpose of this study is to check the effect of applied facility improvement projects through a survey to residents on the significance degree of improving the residential environment and the satisfaction degree of current residential environment. Moreover, this study aims to draw out the direction of the residential environment improvement. At first, for this purpose, a survey to the residents of old and deteriorated public rental housing in the country was conducted. In addition, the mean value analysis on the satisfaction degree and significance degree was done, and the factor analysis was conducted for the distinction between types of items. As a result, 29 items of residential public space for residential environment improvement were divided into six factors and 28 items for generation of each units were divided into four factors. The mean value of the satisfaction degree and significance degree was compared. In conclusion, the design direction of environment improvement projects in the future was suggested with the result of the survey.

The aim of this study was to determine the variation of phenolic compounds in common and tartary buckwheats collected from China, Japan and Korea. Two buckwheat varieties of each country were cultivated using nutrient solution and vermiculite in the greenhouse from February to May, 2012 and harvested at two-week intervals. Phenolics such as chlorogenic acid, C-glycosylflavones (orientin, isoorientin, vitexin, and isovitexin), rutin, and quercetin were quantified using high performance liquid chroma-tography (HPLC). At 17, 29, 44, 58, and 72 days after sowing (DAS), before harvesting each organs, rutin content of cultivars from China and Korea at 17 DAS was the highest (mean 43.63 and 39.95 mg?g–1 DW, respectively) than that of 29 and 44 DAS. However, two varieties from Japan at 44 DAS were documented maximum; whereas, the amount of rutin in “Hokkai T10” harvested at 44 DAS (58.36 mg?g–1 DW) was the highest of all cultivars. Rutin level in the leaves and stems at 72 DAS were comparatively higher than at 58 DAS. The highest of rutin content was found at 72 DAS (73.33 mg?g–1 DW) in “Hokkai T10” leaves followed by “Daegwan No.3-3” (61.13 mg?g–1 DW), “rice tartary” (53.89 mg?g–1 DW). Rutin content of flowers was presented as the highest amount in “Hokkai T10” at 72 DAS (88.3 mg?g–1 DW) was approximately 14-fold higher than that of 58 DAS (6.44 mg?g–1 DW). However, rutin content of flower in “Xiqiao No.2” was 3-fold higher at 72 DAS than at 58 DAS. Rutin and total phenolic compounds content in flowers, leaves, and stems were higher in the order. The content of four C-glycosylflavones in common buckwheat was higher than those in tartary buckwheat, but rutin content which accounted >90% of the total phenolic compounds was higher in tartary buckwheat. The highest amounts of chlorogenic acid and quercetin were measured in the flower of “Xiqiao No.2” (6.85 and 11.69 mg?g–1 DW, respectively). Based on these results, the presence of different phenolic compounds in all the varieties of buckwheat confirmed that it can be regarded as a potent source of functional foods.

The bacterial flagellar hook is a tubular helical structure made by the polymerization of multiple copies of a protein, FlgE. Here we report the structure of the hook from Campylobacter jejuni by cryo-electron microscopy at a resolution of 3.5 Å. On the basis of this structure, we show that the hook is stabilized by intricate inter-molecular interactions between FlgE molecules. Extra domains in FlgE, found only in Campylobacter and in related bacteria, bring more stability and robustness to the hook. Functional experiments suggest that Campylobacter requires an unusually strong hook to swim without its flagella being torn off. This structure reveals details of the quaternary organization of the hook that consists of 11 protofilaments. Previous study of the flagellar filament of Campylobacter by electron microscopy showed its quaternary structure made of seven protofilaments. Therefore, this study puts in evidence the difference between the quaternary structures of a bacterial filament and its hook., The bacterial flagellar hook is made up of many copies of the protein FlgE. Here, the authors report the full structure of the hook from Campylobacter jejuni and show that its overall structure is different from that of the previously published filament.

A periplasmic flagellar chaperone protein, FlgA, is required for P-ring assembly in bacterial flagella of taxa such as Salmonella enterica or Escherichia coli. The mechanism of chaperone-mediated P-ring formation is poorly understood. Here we present the open and closed crystal structures of FlgA from Salmonella enterica serovar Typhimurium, grown under different crystallization conditions. An intramolecular disulfide cross-linked form of FlgA caused a dominant negative effect on motility of the wild-type strain. Pull-down experiments support a specific protein-protein interaction between FlgI, the P-ring component protein, and the C-terminal domain of FlgA. Surface plasmon resonance and limited-proteolysis indicate that flexibility of the domain is reduced in the covalently closed form. These results show that the structural flexibility of the C-terminal domain of FlgA, which is related to the structural difference between the two crystal forms, is intrinsically associated with its molecular chaperone function in P-ring assembly.

최근 우리가 살고 있는 정보화 사회의 가장 중요한 화두 중 하나로 "스마트"가 떠오르고 있으며 통신 및 사회간접자본 분야 등을 포함한 사회의 여러 영역이 이 주제로 빠르고 접근하고 있다. 국내에서는 전력분야에서의 우선접근이 비교적 성공적인 평가를 받고 있으며 물공급 분야는 이제 막 그 첫발을 내 딛고 있는 것이 현실이다. 이러한 관점에서 본 연구는 "스마트 워터 그리드" 서비스를 위한 프레임? 개발에 그 목적이 있다. 연구의 절차로, 우선 국내외 관련 연구가 조사되었고, "스마트 워터 그리드" 서비스를 구성하는 4 기술요소가 정의 되었다. 4 기술요소분야 각각에 대해 프레임? 모델링이 수행되었고 그 결과로 각각에 대한 TRM이 제시된다. 또한 4 요소영역을 아우르는 전체 서비스에 대한 종합적 TRM이 제시되고 본 논문에서 제시되는 프레임? 모델과 유사 모델을 비교하면서 차별성 있는 연구내용의 전개와 두 모델의 연계컨셉이 정의되었다. 엔터프라이즈 통합모델, 즉, 매크로 레벨부터 마이크로 레벨 적용과 서비스를 온전히 커버하기위해 필요한 두 모델의 합체운영 컨셉과 이러한 상호연계성 위에서 작용하는 마이크로 레벨 모델의 현실화를 통해 물관리분야에서의 스마트화 구현에 현 논문이 다소간 기여하기를 기대한다. 【The current society, namely information society is now moving to a specific topic which is SMART. In this sense, recently a variety of social areas including communications and SOC domains are moving fast to this topic. In Korea, The electric power area has been doing a pioneering job relatively successfully and the water supply area is just now taking the first step. The purpose of this research is to develop a technical Framework for Smart Water Grid Service. Related researches has been studied and the 4 constituting technical element areas were defined first. For each of the four areas, a framework modeling was fulfilled and as a result, a TRM(Technical Road Map) was suggested for each of the area. Finally, an Enterprise TRM covering all of the 4 areas was described. Furthermore, the currently suggested Framework model was compared to a related model and it was found that the integration of the models is desirable to wholly cover from Macro to Micro level applications and services. It is expected that the current approach contribute, more or less, to the smart implementation in the areas of water management.】

CHO (Chinese Hamster ovary) cells are widely used for biotechnology and biomedical purposes, and now the EST library database of CHO cells is built. Based on this, the construction of the hamster genome library is under exertion. Though the transformation-associated recombination (TAR) cloning method is accounted as an innovative cloning technology without the construction of the genome library in human and mouse, there has been no trial to isolate the genomic fragment from hamster genome by TAR cloning. In this study, approximately 31 kb of hamster genomic fragment was isolated from the normal human/hamster mono-chromosomal somatic cell line (UV5HL9-5B) using universal hooks of rodent repeats sequence of B1 and B2 by TAR cloning. This fragment was analyzed by bioinformatics tools related to the genome alignment for the similarity analysis among rodent and primate, and was classified into rodents by phylogenetic analysis. One putative gene was found in this region which has homology with the human c14orf4 gene. A zinc finger protein domain was found in the translated hamster ORF. Therefore, we suggest that TAR cloning technique can be applied in CHO cells using mouse genomic information, and it can lead to the establishment of the hamster genome database.

The Four Major Rivers Restoration Project (4MRRP), one of the largest river rehabilitation projects in Korea, has being carried out during the last three years. 0.57 billion m3 of sediment was dredged to widen and deepen the channel along four major rivers, the Han, Nakdong, Geum, and Youngsan rivers. As a result of reshaping the natural channel to a trapezoidal channel, and the construction of 16 weirs, the change of longitudinal slope of the river was inevitable. The distribution of bed materials was also changed, due to dredging. Therefore, the rivers were totally disturbed, and the stability of the rivers could not be assured. In particular, the Nakdong river, the second largest river in Korea, has the characteristics of an alluvial channel. Degradation of the main channel bed caused bank erosion, and head-cut phenomena in many tributaries. Deformations of the main channels could be observed all along the river. Long-term simulation of the channel evolution and prediction of the stability of the Nakdong river have to be examined, to cope with the instability of the river, which could lead to unexpected river disasters. This study deals with the methodology of uncertainty improvement, in analysis of the simulation and confirmation with field survey data. Methodology of uncertainty improvement in description of weir, whose discharge coefficient is unknown, in a river was suggested.

Contents of soyasaponin group B were compared according to two regions and ten varieties by HPLC. Those compounds were known to be beneficial for health. After soyasaponins were isolated and identified, those isolated compounds were used for HPLC analysis. The contents of soyasaponin were very different by regions but highest in the soybean with black seed coat. It was appeared that environmental difference for soybean growth could strongly change of soyasaponin contents.

The Korean government required the mandatory ratio of public housing including the housing unit for elderly in February 2012 and the number of them is expected to increase accordingly. To prepare for an aged society, these enabling ubiquitous technology will be able to support efficient health care services, which was mentioned in various studies. Therefore, the aim of this study is to draw the design elements for an apartment for providing health care services according to the degree of independence of elderly people and to grasp the current situation and work out tactics by the evaluation of four actual cases. In housing unit in the elderly housing project, design elements supporting amenity improvement was rated to the highest importance, however, in reality, was reflected at lower rate while the risk management plan for public space was applied at the highest rate. Design elements required by new technology such as health monitoring and community management with outside world are still not reflected, however, in order to realize the concept of 'aging in place', health care services in various aspects should be considered in housing planning.

Within twenty years, Permanent Affordable Housing provided for people's security of housing in late 1980's yields the principles of equity with tenant's in new one supplied, thus being confronted by the requirements that existing welfare service for tenants should be improved. Reflecting on these, this study means to prepare the basic data for the welfare policy as applying welfare service types on basis of housing locational characteristics, tenants tier compared with welfare service needs of permanent affordable housing tenants. For achieving this aim, the range and mixed use mechanism of welfare service are investigated as reviewing the related research and findings. Based on this investigation, 7 types of welfare service(Independence, Half-support, Child care, Juvenile, Self-support, Social-mix, and Single household) are established. On the analysis of survey, the welfare service needs are investigated as grouping with locational characteristics and survey target. In addition, the welfare service types are reorganized by analysis of tenant's demographic and locational characteristic on each housing and are compared with tenants needs. Although, the demographic of permanent affordable housing generally shows that the tenants are constituted with aged people, the housing with high ratio of children and juvenile can be applied with Child Care type and Juvenile type. As a result of comparison, the ratio of independence type, juvenile type, and single household type are more on the large housing and housing on metropolitan area, and the ratio of half-support type and child care type are more on the small housing and housing on small city area.